From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 309 invoked by alias); 24 Nov 2012 12:47:54 -0000 Received: (qmail 32711 invoked by uid 48); 24 Nov 2012 12:47:40 -0000 From: "ktietz at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/55171] [4.7/4.8 Regression] incorrect virtual thunk on mingw Date: Sat, 24 Nov 2012 12:47:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c++ X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: ktietz at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: Status Last reconfirmed Ever Confirmed Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2012-11/txt/msg02253.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55171 Kai Tietz changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2012-11-24 Ever Confirmed|0 |1 --- Comment #7 from Kai Tietz 2012-11-24 12:47:37 UTC --- Yes, the issue here is the generation of patterns - like movl (%ecx), %eax addl -12(%eax), %ecx - for thunks. The following patch solves this issue for me. Index: i386.c =================================================================== --- i386.c (Revision 193669) +++ i386.c (Arbeitskopie) @@ -9567,6 +9567,8 @@ tree decl = current_function_decl, fntype = TREE_TYPE (decl); bool fastcall_p = lookup_attribute ("fastcall", TYPE_ATTRIBUTES (fntype)) != NULL_TREE; + bool thiscall_p + = lookup_attribute ("thiscall", TYPE_ATTRIBUTES (fntype)) != NULL_TREE; bool static_chain_p = DECL_STATIC_CHAIN (decl); int regparm = ix86_function_regparm (fntype, decl); int drap_regno @@ -9577,10 +9579,13 @@ if ((regparm < 1 || (fastcall_p && !static_chain_p)) && drap_regno != AX_REG) regno = AX_REG; - else if (regparm < 2 && drap_regno != DX_REG) + else if (thiscall_p + && !static_chain_p && drap_regno != DX_REG) + regno = DX_REG; + else if (regparm < 2 && !thiscall_p && drap_regno != DX_REG) regno = DX_REG; /* ecx is the static chain register. */ - else if (regparm < 3 && !fastcall_p && !static_chain_p + else if (regparm < 3 && !fastcall_p && !thiscall_p && !static_chain_p && drap_regno != CX_REG) regno = CX_REG; else if (ix86_save_reg (BX_REG, true)) @@ -11092,12 +11097,15 @@ return R11_REG; else { - bool is_fastcall; + bool is_fastcall, is_thiscall; int regparm; is_fastcall = (lookup_attribute ("fastcall", TYPE_ATTRIBUTES (TREE_TYPE (cfun->decl))) != NULL); + is_thiscall = (lookup_attribute ("thiscall", + TYPE_ATTRIBUTES (TREE_TYPE (cfun->decl))) + != NULL); regparm = ix86_function_regparm (TREE_TYPE (cfun->decl), cfun->decl); if (is_fastcall) @@ -11110,6 +11118,12 @@ } return AX_REG; } + else if (is_thiscall) + { + if (!DECL_STATIC_CHAIN (cfun->decl)) + return DX_REG; + return AX_REG; + } else if (regparm < 3) { if (!DECL_STATIC_CHAIN (cfun->decl)) @@ -25046,7 +25060,7 @@ fntype = TREE_TYPE (fndecl); ccvt = ix86_get_callcvt (fntype); - if ((ccvt & (IX86_CALLCVT_FASTCALL | IX86_CALLCVT_THISCALL)) != 0) + if ((ccvt & IX86_CALLCVT_FASTCALL) != 0) { /* Fastcall functions use ecx/edx for arguments, which leaves us with EAX for the static chain. @@ -25054,6 +25068,8 @@ leaves us with EAX for the static chain. */ regno = AX_REG; } + else if ((ccvt & IX86_CALLCVT_THISCALL) != 0) + regno = DX_REG; else if (ix86_function_regparm (fntype, fndecl) == 3) { /* For regparm 3, we have no free call-clobbered registers in @@ -34713,8 +34729,10 @@ else { unsigned int ccvt = ix86_get_callcvt (TREE_TYPE (function)); - if ((ccvt & (IX86_CALLCVT_FASTCALL | IX86_CALLCVT_THISCALL)) != 0) + if ((ccvt & IX86_CALLCVT_FASTCALL) != 0) tmp_regno = AX_REG; + else if ((ccvt & IX86_CALLCVT_THISCALL) != 0) + tmp_regno = DX_REG; else tmp_regno = CX_REG; }